Sharpening device for bush-hammers.



G. K. GEORGE & T. J. MURPHY. S'HARPENING DEVICE FOR BUSH HAMMERS.

APPLICATION FILED NOV.l3, 1911.

Patented Nov. 19, 1912.

attozueu o abrasive material, preferably carborundum.

To all whom 'it may concern:

declare the following to be a full, clear,-and

CORTIS KIMBALL eEoRG i-i' Ann HAMPSHIRE, assreuons or NEW HAMPSHIRE.

SHABPENING DEVICE f s peciiication of Letters Patent.

FOR BUSH-HAMMERS.

. Patented Nov. 119, 1912.

Application fileditovember 13, 1911. Serial No. 660,048

Be it known that we, CORTIS KIMBALL GEORGE and TIMOTHY JAMES MURPHY, citizens of the United States, residing at Milford, in the county of Hillsboro and State of New Hampshire, have invented certain new and useful Improvements in Sharpening Devices for Bush-Hammers; and we do exact description of the invention,such as will enable others skilled inthe art to which it appertains to make and use the same.

This invention relates to improvements in sharpening devices for bush hammers.

One object of the invention is to provlde a sharpening device of this character by means of which all the blades of the hammer may be simultaneously sharpened without removing the same thus greatly simplifying and expediting the operatlon of sharpening the hammer.

With this and other objects in view, the invention consists ofcertain novel features of construction, and the combination and arrangement of parts as will be more fully described-and claimed.

In the accompanyingdrawings; Figure 1 is a side view of our improved sharpening device; Fig. 2 is a central longitudinal sectional view thereof; Fig. 3 is an end view of the same; Fig. 4 is a side view of one of the grinding disks; Fig. 5 is a similar view of one of the paper spacing disks arranged between the grinding disks.

Referring more particularly to the drawing, 1 denotes the shaft of the sharpening device, said shaft being preferably hollow and is supported and driven in any suit-able manner. On the shaft is arranged a flange in the form of a stop collar 2 secured in position by a set screw 3. The opposite end of the shaft 1 is threaded and on said threaded end is screwed a clamping nut a.

Arranged on the shaft between the collar 2 and the nut 4 are a plurality of grinding disks 5 of which there may be any desired number, said disks being formed of suitable The sides of the disks are beveled at their outer edges to form inverted V-shaped grinding surfaces and the disks are spaced a slight distance apart by 'paper spacing disks 6, the diameter of which corresponds to the diameter of the disks between the inner edges of the beveled grinding surfaces as shown. The purpose of the paper disks will be hereinafter described On the shaft between the outer grinding disks 5 and the stop collar 2 and clamping nut 4 are arranged clamping disks or plates 7 which are preferably formed of wood so that the same may be readily trimmed down as the grinding disks are worn away. The edges of the clamping disks 7 are preferably beveled outwardly as shown. In thus arranging the grinding disks they may be rigidly clamped together in operative position on the shaft between the clamping nut 4 and the collar 2 by screwing said nut up on theshaft as will be readily understood.

By constructing and arranging the grinding disks as herein shown and described it will be seen that all of the blades or cuts of the hammer may be v simultaneously sharpened on one end without removing any of the blades thus greatly facilitating the sharpening operation. The paper spacing disks 6 between the grinding disks prevent grinding off the edges of the hammer blades when said edges reach the extreme depth of the spacesbetween the grinding surfaces of the disks and also the proper depth of bevel to be maintained on the grinding surface of the disks.

By the use of our improved grinding tool the edges of the hammer blades will be uniformly and evenly sharpened or ground from the very edge inwardly and in a much shorter time than is required when each blade is separately ground.

From the foregoing description taken in connection with the accompanying drawings the construction and operation of the invention will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion and the minor details of construction may be resorted to without departing from the principle or sacrificing any of the advantages of the invention as claimed.

Having thus described our invention, what we claim is;

A sharpening device for bush hammers comprising a driving shaft with a series of grinding disks mounted thereon and formed of abrasive material and provided on their circumferences with oppositely disposed beveled edges, constructed in V-shape form,

disks of soft material interposed between the grinding disks and having their peripheries terminating at the inner edges of the V shaped grinding surfaces, fibrous plates arranged on the shaft and adapted to contact with the two end disks of the series, said fibrous plates having beveled edges contiguous with the outer bevels on the two end disks, a collar on the shaft contacting with 10 one of the plates, and a nut also on the shaft contacting with theother plate whereby to clamp the series of grinding disks together. 1

In testimony whereof we have hereunto set our hands in presence .of two subscribing witnesses.

CORTIS KIMBALL GEORGE. TIMOTHY JAMES MURPHY. Witnesses:

CHARLES L. Loon, HEM'MEL BAUM. 

